RRS John Murray JM2A/81 (B/2/81)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS John Murray (74MJ)
Cruise identifierJM2A/81 (B/2/81)
Cruise period1981-03-16 — 1981-03-24
Port of departureBarry, United Kingdom
Port of returnPlymouth, United Kingdom
Objectives1) To continue the monitoring cruises in the Bristol Channel and Severn Estuary

2) To analyse the seawater and suspended particulate matter for trace metals in Swansea Bay as part of a continuing study of water quality in the area of Scarweather Sands and its association with the transportation of toxic contaminant bound to particulate matter from areas known for effluent discharge.

3) To test the new codend systems, opening and closing devices and new configurations of equipment fitted to the Double Lowestoft Longhurt System.
Chief scientistBob Williams (Institute of Marine Environmental Research, Plymouth)
Cruise reportRRS John Murray JM2A/81 (B/2/81) cruise report john_murray2a_81.pdf (0.10 MB) 
Ocean/sea areas 
GeneralIrish Sea and St. George's Channel
Track chartsRRS John Murray JM2A/81 (B/2/81) cruise track — trk2567a.html RRS John Murray JM2A/81 (B/2/81) cruise track — trk2567b.html
Physical oceanography 
Surface measurements underway (T,S)
Water bottle stationsQuantity: number of stations = 15
Description: surface only
Suspended matter
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of stations = 2
Particulate organic matter (inc POC, PON)Quantity: number of stations = 2
PhytoplanktonQuantity: number of stations = 2
ZooplanktonQuantity: number of stations = 4
Description: energy transfers,population structures
SestonQuantity: number of stations = 2
Pelagic bacteria/micro-organismsQuantity: number of samples = 50